Emissions monitoring and tracking system

ABSTRACT

A portable subsystem carried by the inspector includes an identification scanner, an emissions sensor and a portable data collector. An inspector identifies the release point by use of a portable scanner and then tests the release point for leaks. The portable data collector stores the identification along with the emissions test data. At periodic intervals the portable data collector is connected to a main computer and the stored data is uploaded. The main computer analyzes the uploaded data for a pass or fail of the release point of the emissions test and issues the appropriate comparison results. Additionally, the severity of the leak is determined and remedial action is specified. This remedial action includes issuance of a repair report and updating the repair schedule, updating the inspection schedule for reinspection after repairs are completed and updating the inspection history. The computer maintains data sufficient to generate reports tailored to the requirements of government agencies.

This is a divisional of copending application Ser. No. 07/595,262 filedon Oct. 9, 1990 now U.S. Pat. No. 5,099,437.

BACKGROUND OF THE INVENTION

The invention is generally related to sensors and, more particularly, tosystems for detecting hydrocarbon emissions and for tracking the historyof equipment tested for emissions.

The desirability of reducing harmful hydrocarbon emissions has long beenrecognized. Accurate and reliable emissions monitoring has a highpriority in many geographical areas and progressively more stringentemission control standards have been promulgated, particularly in highair pollution areas. For example, Rule 1173 of the State of Californiarelates to the Fugitive Emissions of Volatile Organic Compounds and hasmonitoring, record keeping and reporting requirements. The rule is meantto apply to petrochemical facilities, including refineries, pumpingstations and storage facilities. Hydrocarbon emissions are to bemonitored, identified and recorded and if the emissions exceed certainlimits, repair action is to be undertaken.

Federal Rule 49 (37 CFR §191 and §192) is another emission standardwhich addresses somewhat different emissions but nevertheless imposesmonitoring, recording and reporting requirements on petrochemicalfacilities.

In general, these rules require that each possible point of escape forhydrocarbons, or "release point", in a petrochemical facility beidentified, monitored and tracked. That is, each fitting, joint, packinggland, flange and other possible points where hydrocarbons could escapemust be monitored and tracked. Leak limits have been established and inthe event that emissions from a release point exceed the limit,corrective action must be taken. Under California Rule 1173, the type ofcorrective action depends upon the severity of the leak. For example, aslight leak, but one that exceeds the threshold nevertheless, may besubject to repair within fourteen days of detection while a massiveliquid leak may be subject to immediate repair.

Tracking the leak history of a release point is important because thefavorable leak history of a release point may, under California Rule1173, qualify that release point for a reduced monitoring schedule.Conversely, a poor leak history may result in a requirement that thepart be replaced or that the joint be reformed or that other correctivemaintenance action be taken.

One prior technique for monitoring such emissions involved manualsensing and recording. Emissions were sensed by a portable vaporanalyzer, the results were displayed by that analyzer and the operatorwould then record the results manually. Such a system had a potentialfor operator error, including mis-identification of the release point,incorrectly recording the release point identification, misreading thesensor, incorrectly recording the sensed emissions, illegibility ofwriting, and other possible errors.

One desired effect of the above-mentioned emission standards is to causeincreased automation of monitoring and tracking efforts. Methodologiesinvolving automation of as many steps as possible are preferable. It isbelieved that such automation will result in more consistent andreliable monitoring of emissions and record-keeping. Optimally, theequipment used for identifying, monitoring, recording and reportingwould define a closed system in which human error would be minimized.Direct communication between all system components involved inidentification of the release point under test, sensing emissions fromthat release point, data recording and processing, and report generationwould provide an integration of the system to an extent that the systemwould be more reliable and operator error would be minimized. Theinvention fulfills these needs.

SUMMARY OF THE INVENTION

Briefly and in general terms, the present invention provides a new anduseful emissions monitoring and tracking system. The invention isdirected to a system for identifying various release points, inspectingthe release points for emissions, tracking their inspections, trackingrepairs, and creating records and reports of these activities. Inaccordance with the invention, the system includes a portable subsystemcarried by the inspector which includes an identification scanner, anemissions sensor and a portable processor for storing certain inspectiondata.

Identification tags are attached to the release points to be inspected.The inspector identifies the release point by scanning theidentification tag with a portable scanner. The inspector then tests therelease point for emissions. The portable processor stores theidentification data along with the emissions test data. At periodicintervals the portable processor is connected to a main computer toupload the stored data. The main computer analyzes the uploaded data todetermine if each release point passed or failed the emissions test andissues the appropriate test results. The main computer may also storethe test data along with the inspection date, identification code, testresults, test equipment identification and inspector identification.

Additionally, the severity of the leak is determined and the requiredremedial action is specified. This remedial action may include addingthe release point to a repair list, updating the repair schedule,updating the inspection schedule for re-inspection after repairs arecompleted and updating the maintenance and inspection histories. Themain computer is capable of generating reports tailored to therequirements of interested government agencies. The main computer alsotracks the repair history of individual equipment items and can reporton an item requiring frequent repairs. This main computer is capable ofperforming the above functions in cooperation with commerciallyavailable programs for scheduling maintenance or other activities.

These and other objects and advantages of the invention will becomeapparent from the following more detailed description, when taken inconjunction with the accompanying drawings of illustrative embodiments.

DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram of an emissions monitoring and tracking system inaccordance with the principles of the present invention showing abarcode on a release point, a barcode scanner, a volatile organiccompounds analyzer, a portable data collector with an emissions readingdisplayed on its front panel and a main computer;

FIG. 2 is a rear view of the portable processor of FIG. 1 showing anexample of cable connections; and

FIG. 3 is a block diagram of an emissions monitor and tracking method inaccordance with the invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

In the following description, like reference numerals will be used torefer to like or corresponding elements in the different figures of thedrawings. Referring now to the drawings, and particularly to FIG. 1,there is shown an emissions monitoring and tracking system 10 inaccordance with the principles of the invention. A joint 12 is shownwhich connects two pipes used to conduct hydrocarbons such as petroleumand petroleum by-products. The joint is referred to as a "release point"and under various environmental rules and regulations, is subject toperiodic testing for leakage of the hydrocarbons conducted. Anidentification tag 14 has been attached to the joint in a permanentmanner such as by use of rivets, an adhesive, a protected container orscrews. In the embodiment shown, the tag is in the form of a barcode.The identification tag may be formed of different materials dependingupon the substances conducted by the item to which it is attached.Materials resistant to deleterious environments should be used in theidentification tag. In the case where hydrocarbons are conducted, thetag may be formed of oxidized aluminum. The bar code may be imbedded inthe aluminum and then laminated. The identification tag is attached ator near the item to be inspected. In the example of the joint betweentwo pipes as shown, the identification device could also be strapped toone pipe near the joint. Where the release point permits, the tag may beattached by brads, chain or some other locking device. While a barcodeidentification system is shown and described above, other systems suchas a magnetic identification system may also function adequately.

In one embodiment, where the system in accordance with the invention isto be applied to a refinery having numerous joints, fittings, packingglands, flanges and other types of release points, the identificationtag carries a unique identification code. Each release point in thesystem therefore has a unique identification code and can be trackedindividually. In one embodiment, bar code symbology Code 39 was used.The selection of the width and number of the bar code elements is wellknown to those skilled in the art and no further explanation is providedhere.

Also shown in FIG. 1 is a portable barcode scanner 16. In the embodimentshown, the scanner is a laser type capable of reading the bar code froma distance. The output of the laser barcode scanner 16 along line 17 isa signal representative of the barcode value scanned. Such a scanner isvery light in weight and can be easily transported from release point torelease point by many means, one of which is a holster worn on the beltof the inspector.

The output of the laser barcode scanner is coupled to a portable datacollector (PDC) 24. The portable data collector 24 receives theidentification signal from the barcode scanner on line 17 and formats itas necessary into identification data for storage in an internal storagemedium such as a random access memory. In one embodiment, the portabledata collector 24 includes a display 26 for indicating the sensedemissions data which, in this case, is displayed as parts per million(ppm). Laser barcode scanners coupled with data collectors are known inthe art, one example is the PC-WAND model 800 from Unitech Computer Co.,Ltd., Paramount, Calif.

Further referring to FIG. 1, a portable organic emissions sensor 18 isshown. The analyzer includes a movable probe 20 and an output line 22which carries a signal representative of the vapors sensed and analyzedby the analyzer 18. Such an analyzer may provide a signal representativeof the total organic vapor concentrations and qualitative analysis asselected. A vapor analyzer or emissions sensor such as the Century OVA108 Portable Organic Vapor Analyzer sold by The Foxboro Company, EastBridgewater, Mass., is an example of an emissions sensor usable inaccordance with the invention. The Foxboro OVA 108 weighs approximately26 kilograms (12 pounds). The portable data collector 24 receives thesense signal from the emissions sensor 18 on line 22 and stores thesense signal as emissions sense data in the memory. In the case of theOVA 108 Analyzer from Foxboro, the sense signal is first converted froman analog signal to a digital signal by means of an analog-to-digitalconverter.

The portable data collector 24 in one embodiment is used to collectvarious forms of data. For example, at the start of an inspection tour,the inspector scans his or her badge barcode and the identificationbarcodes of the emissions sensor and the portable data collector itself.These laser scanner signals are each given a date and time and arestored in the portable data collector 24 as data as pertaining to allfollowing inspections of release points on this tour. When making arelease point inspection, the release point identification tag isscanned, and it and the date and time are stored as data along with theemissions signal from the emissions sensor 18. An end of the presentinspection tour may be indicated to the portable data collector 24 byclosing a switch or other means. After receiving the end of tour signal,new inspector, emissions sensor and portable data collectoridentifications may be entered.

Safeguards may be built into the portable data collector 24, such as atime limit within which signals must be received. In one embodiment, therelease point identification tag is first scanned with the laser scanner16 and upon such scanning, the portable data collector 24 opens a newrecord in its memory. The inspector must then complete an emissionsreading and scan the identification tag a second time within two minutesor the record will not be retained in memory. The second scan of thesame identification tag causes the portable data collector 24 toconclude that a successful inspection has been made and the results areto be stored. Failure to scan the identification tag a second timewithin the two minute limit causes the portable data collector 24 toconclude that an inspection was not successful 43 and no record isstored 45 as shown in FIG. 3. Additionally, audio cues may be providedto the inspector. For example, audible tones may be provided upon eachsuccessful scan of an identification tag.

The portable components of the system 10 are light in weight and may becarried by an inspector from release point to release point. In afurther embodiment, the emissions sensor 18 may be integrated with theportable data collector 24. The portable data collector 24 may beconfigured with harness or belt means, holsters, etc. for carrying bythe inspector, or may be configured with wheels or a cart for mobility,depending on the size and type of the system.

Referring now to FIG. 2, the rear of a portable data collector 24 isshown so that one example of possible cable connections may be viewed.The bar code scanner is connected with a nine-pin, standard serialinterface, RS-232C connector while the emissions sensor is connectedwith an Amthenol five-pin connector. In this embodiment, the connectorused for the laser scanner may also be used as a connector forconnecting the portable data collector 24 to the main computer 28 aswill be described below in more detail.

Thus, as described above and shown in the FIGS., the portable subsystemprovides an indentification and emissions sensing subsystem which isautomated. The inspector's tasks include merely scanning test equipmentbar codes and finding the correct release point at the facility to beinspected. Once the release point is found, the inspector's tasks aresimply mechanical in nature and require no subjective performance. Theinspector simply scans the associated identification tag and thenapplies the emissions sensor to the release point until a reading hasbeen taken. Such automation increases reliability and decreasesinspection time.

Under certain emission control regulations, release points must beinspected periodically and the results of the inspection reported. Insome areas, these reports must be forwarded to the responsiblegovernment agency and in other areas, the reports must be maintained fordiscretionary inspection by the government agency. The release pointsare subject to corrective action in the event of an excessive leak andthe results of such action must also be reported or at least records ofthe results maintained.

Referring now to FIGS. 1 and 3, in the preferred embodiment, the maincomputer 28 determines whether a release point passed or failed aninspection and generates the appropriate written reports. Additionally,an inspection history of each release point may be stored in a magneticmedium for future reference. Report generation may be tailored to theapplicable government requirements and in the preferred embodiment, themain computer 28 also issues repair lists.

A schedule 30 of release points to be inspected is given to theinspector. This schedule may be generated by the main computer 28 from alisting of all the release points in the facility, their locations,their inspection frequency and their inspection histories. A dedicatedscheduling program may be used or a commercially available schedulingprogram such as one which might be used for the entire plant (forexample "Finest Hour" manufactured by Primavera Systems, Inc. having anaddress of Cynwyd, Pa.).

In one embodiment, the main computer 28 is used to track all inspectionsby quarter. During each quarter, a current-quarter database is createdand the test results from the current quarter and the previous fourquarters are retained by the main computer. This arrangement permitstracking test results over a selected period of time for each releasepoint. Certain emissions control regulatory schemes allow a greater timebetween inspections for items which have passed a certain number ofsuccessive quarterly inspections. For example, California Rule 1173permits yearly inspections of a release point which has successfullypassed five successive quarters. Also, release points requiring frequentrepair or parts replacement can be identified. In accordance withCalifornia Rule 1173, in the event that a release point fails aninspection six times within four quarters, the release point must bereplaced with the best available commercial technology/best availablereplacement technology (BACT/BART). The main computer is capable oftracking such a history.

Upon receipt of a portable data collector 24, an emissions sensor 18 andthe schedule, the inspector may scan 32 his or her identification codeand the codes of this equipment by the portable data collector 24itself. The portable data collector 24 will then apply this data to thefollowing emissions test data until an end-of-tour signal is received.The inspector then locates the release point to be inspected and scans34 its previously attached bar code label with the portable scanner 16.This first scanning of the identification tag causes the portable datacollector 24 to open 36 a record. The inspector then tests 38 therelease point for emissions with the emissions sensor 18, 20 until areading has been taken and recorded 40 by the portable data collector.An audible cue may be provided to the inspector by the portable datacollector 24 indicating that the processor has received and recordedemissions test data. The inspector then scans the identification tag ofthe release point a second time 42. The portable data collector 24accepts this second scan and closes 44 the record and stores it forfuture upload. The inspector continues inspecting 46 until the tour isover.

At the end of each day or inspection tour the inspector may upload 48the stored records from the portable data collector 24 to the centralcomputer 28. In the embodiment shown in FIGS. 1 and 2, the cable to thelaser scanner would be removed from the portable data collector 24 and astandard serial cable attached. The serial cable may be connected at itsother end directly to the main computer 28 or other means forcommunicating with the main computer 28.

In the main computer 28, the sense data in the uploaded record for eachinspected release point is compared 50 to a predetermined criterion anda "passed" or "failed" status of that release point for that test isdetermined. In the event that the release point passed the test, itsinspection history is updated 52. In the event that the release pointfailed the test, the severity of the leak is determined 54 and therelease point is added to a repair list 56. Depending upon the severity,different repair schedules 58 can be issued. For example, in the casewhere the leak is greater than 1000 ppm but less than or equal to 10,000ppm, the leak is classified as minor and a fourteen day work order maybe issued. In the case of a leak in a pressure relief device which isgreater than 200 ppm, the leak is classified as major and a five daywork order may be issued. In the case where the leak is greater than10,000 ppm but less than or equal to 50,000 ppm, the leak is classifiedas major and a five day work order may be issued. In the case where theleak is greater than 50,000 ppm but less than or equal to three dropsper minute, the leak is classified as a major leak and a one day workorder may be issued. In the case where the leak is greater than threedrops per minute, the leak is classified as a liquid leak and a one-daywork order may be issued. Also in the case of the last two leakclassifications, a work order requiring replacement with BACT/BART willbe issued if there have been five significant repairs in a continuoustwelve month period.

When the release point is added to the repair list, such action isindicated on its inspection history 52 and failure reports generated 59.When the repairs are completed 60 the leak/repair history is updatedagain 52 and the component is scheduled for reinspection 30. The processfor reinspection of an item is identical to the procedure describedabove. Where repairs or reinspections are not made by the time anotherrepair list is prepared, the unrepaired or uninspected release pointsappear again on the repair list.

In one embodiment, a release point database is set up in the maincomputer 28 wherein each item of equipment is identified along with itsattributes. These attributes might include the following, by way ofexample: an ID number assigned to the item; its bar code tag number;what the item services; the unit number of what the item services;location of the item, whether accessible or inaccessible, and thedrawing number(s) of the plant drawings showing the item; what type ofequipment the item is; whether it is a major or minor component of theplant; the maximum parts per million (ppm) reading allowable for theitem when tested; the inspection frequency (i.e. annually, quarterly,etc.); the number of repairs on the item; the schedule status (i.e. notcurrently scheduled for inspection, passed, or under repair); the old IDnumber of this item if it has been replaced.

Also in this embodiment, a list of inspectors may be kept as a safeguardin the main computer. The information contained in this databaseincludes for each inspector: his or her name, ID number assigned, andthe company the inspector is employed by. This database may be used tokeep track of which inspectors are authorized to make inspections andwhich inspectors inspected what components. The program checks to makesure the identification number is correct and that the inspector is inthe database. If not, data processing is delayed.

The embodiment may also track the portable data collector 24 and theemissions analyzer 18 by the main computer 28 as a safeguard. A databasecontaining the identification numbers, the model numbers, and the serialnumbers is maintained. This information is used to keep track of thecalibration of test equipment. Also, which sensor device was used ineach test is tracked.

A leak/repair history database is maintained and has the followingfields for example: release point identification number; repair duedate; repair that was made; date of repair; work order number; leakclass (minor, major, over 50,000 ppm, liquid leak); repair complete,needs reinspection. The fields of this database are updated as to eachleak found and work order issued. It is also updated as work orders arecompleted. Repair schedules and release point reinspection schedules aregenerated. In the latter case the process is repeated for repairedequipment as discussed above.

Periodically, inspection history and leak/repair history reports may becreated 62 based on the data residing in the main computer 28. Thereports can be specially formatted for submission to the governmentagencies that may require such reporting.

It will be apparent from the foregoing that, while particular forms ofthe invention have been illustrated and described, various modificationscan be made without departing from the spirit and scope of theinvention. Accordingly, it is not intended that the invention belimited, except as by the appended claims.

What is claimed is:
 1. An apparatus for monitoring hydrocarbon emissionsfrom an emissions release point, comparing the monitored emissions to athreshold, and reporting the comparison results, the apparatuscomprising:an identification code disposed at the emissions releasepoint to identify the release point; a portable data entry device intowhich the identification code is entered, the data entry deviceproviding an identification signal representative of the identificationcode; a portable sensor which senses the hydrocarbon emissions from therelease point and provides a sense signal representative of those sensedemissions; a portable data collector coupled to the data entry deviceand to the sensor to receive the identification signal and the sensesignal and to record the identification and sense signals as data; and amain computer which receives the recorded data from the portable datacollector and compares the sense data to a predetermined threshold todetermine if the sense data exceeds the threshold and reports the resultof the comparison and the identification code of the emissions releasepoint.
 2. The apparatus of claim 1 wherein the identification code iscarried on a label attached at the release point.
 3. The apparatus ofclaim 1 wherein the main computer further issues a repair report whenthe sense signal data exceeds the threshold.
 4. The apparatus of claim 1wherein the main computer generates a history of the release pointcomprising each date that the portable sensor sensed the emissions andthe results of each comparison and updates that history for eachcomparison.
 5. The apparatus of claim 1 wherein the portable datacollector also records the date and time when it records theidentification and sense signals, and the main computer receives thedate and time and updates the history of the release point.
 6. Theapparatus of claim 1 wherein the identification code is unique to therelease point.
 7. The apparatus of claim 1 wherein the portable datacollector opens a record upon receiving a first identification signal ofthe emissions point, records the identification signal and the sensesignal as data and closes and stores the record upon receipt of a secondidentification signal; andthe main computer receives the record, storesthe record, and compares the sense data of the record to thepredetermined threshold.
 8. The apparatus of claim 7 wherein theportable data collector closes and stores the record only if it receivesthe second identification signal within a predetermined time afterreceiving the first identification signal.
 9. Apparatus for monitoringhydrocarbon emissions from an emissions release point, comparing themonitored emissions to a threshold, and reporting the comparisonresults, the apparatus comprising:an identification code disposed at theemissions release point to identify the release point; a portable dataentry device into which the identification code is entered, the dataentry device providing an identification signal representative of theidentification code; a portable sensor which senses the hydrocarbonemissions from the release point and provides a sense signalrepresentative of those sensed emissions; a portable data collectorcoupled to the data entry device and to the sensor to receive theidentification signal and the sense signal and to record theidentification and sense signals as data in a record initiated by theidentification signal wherein the portable data collector also recordsthe date when it records the data; and a main computer selectivelycoupled to the portable data collector which receives the recorded datawhen coupled to the portable data collector, compares the received sensedata to a predetermined threshold to determine if the sense data exceedsthe threshold, reports the result of the comparison, maintains anemissions history of the release point and updates the history of therelease point, and issues a repair report in the event that the sensesignal data exceeds the threshold.
 10. The apparatus of claim 9 whereinthe history of the release point comprises each date that the portablesensor sensed the emissions and the results of each comparison.
 11. Theapparatus of claim 10 wherein the identification code is unique to theemissions release point.
 12. The apparatus of claim 9 wherein theportable data collector opens a record upon receiving a firstidentification signal of the emissions release point, records theidentification signal and the sense signal as data, and closes andstores the record upon receipt of a second identification signal; andthemain computer receives the record, stores the record, and compares thesense data of the record to the predetermined threshold.
 13. Theapparatus of claim 12 wherein the portable data collector will not closeand store the record if the second identification signal is not receivedwithin a predetermined time after receiving the first identificationsignal.
 14. A method for monitoring hydrocarbon emissions from anemissions release point, comparing the monitored emissions to athreshold, and reporting the comparison results, the method comprisingthe steps of:assigning an identification code to the release point;entering the assigned identification code into a portable data entrydevice at the release point and providing an identification signalrepresentative of the identification code entered; sensing hydrocarbonemissions from the release point with a portable emissions sensor andproviding an emissions signal representative of the sensed emissions;receiving the identification signal and the emissions signal andrecording the signals as data; transferring the recorded identificationand emissions data to a main computer; comparing the sensed emissionsdata of the received record to a predetermined threshold in the maincomputer to determine if the threshold has been exceeded, and reportingthe result of the comparison; and storing the result of the comparisonwith the identification data.
 15. The method of claim 14 furthercomprising the step of issuing a repair report when the sensed emissionsdata exceeds the predetermined limit.
 16. The method of claim 14 furthercomprising the step of generating a history of the release pointcomprising each date that the portable sensor sensed the emissions andthe results of each comparison.
 17. The method of claim 14 furthercomprising the steps of:recording the date when the identification andsense signals are recorded as data; transferring the recorded date,identification, and emissions data to the main computer; and storing theresult of the comparison, the identification data and the date.
 18. Themethod of claim 14 wherein the step of assigning an identification codecomprises assigning a unique identification code to the emissionsrelease point.
 19. The method of claim 14 further comprising the stepsof:opening a record upon receiving a first identification signal of theemissions point; recording the identification signal and the sensesignal as data; and closing and storing the record upon receipt of asecond identification signal.
 20. The method of claim 19 wherein thestep of closing and storing the record occurs only when a secondidentification signal is received within a predetermined time afterreceiving the first identification signal.